Identification of a PRPF4 loss-of-function variant that abrogates U4/U6.U5 tri-snRNP integration and is associated with retinitis pigmentosa

TY - JOUR

T1 - Identification of a PRPF4 loss-of-function variant that abrogates U4/U6.U5 tri-snRNP integration and is associated with retinitis pigmentosa

AU - Linder, Bastian

AU - Hirmer, Anja

AU - Gal, Andreas

AU - Rüther, Klaus

AU - Bolz, Hanno Jörn

AU - Winkler, Christoph

AU - Laggerbauer, Bernhard

AU - Fischer, Utz

PY - 2014

Y1 - 2014

N2 - Pre-mRNA splicing by the spliceosome is an essential step in the maturation of nearly all human mRNAs. Mutations in six spliceosomal proteins, PRPF3, PRPF4, PRPF6, PRPF8, PRPF31 and SNRNP200, cause retinitis pigmentosa (RP), a disease characterized by progressive photoreceptor degeneration. All splicing factors linked to RP are constituents of the U4/U6.U5 tri-snRNP subunit of the spliceosome, suggesting that the compromised function of this particle may lead to RP. Here, we report the identification of the p.R192H variant of the tri-snRNP factor PRPF4 in a patient with RP. The mutation affects a highly conserved arginine residue that is crucial for PRPF4 function. Introduction of a corresponding mutation into the zebrafish homolog of PRPF4 resulted in a complete loss of function in vivo. A series of biochemical experiments suggested that p.R192H disrupts the binding interface between PRPF4 and its interactor PRPF3. This interferes with the ability of PRPF4 to integrate into the tri-snRNP, as shown in a human cell line and in zebrafish embryos. These data suggest that the p.R192H variant of PRPF4 represents a functional null allele. The resulting haploinsufficiency of PRPF4 compromises the function of the tri-snRNP, reinforcing the notion that this spliceosomal particle is of crucial importance in the physiology of the retina.

AB - Pre-mRNA splicing by the spliceosome is an essential step in the maturation of nearly all human mRNAs. Mutations in six spliceosomal proteins, PRPF3, PRPF4, PRPF6, PRPF8, PRPF31 and SNRNP200, cause retinitis pigmentosa (RP), a disease characterized by progressive photoreceptor degeneration. All splicing factors linked to RP are constituents of the U4/U6.U5 tri-snRNP subunit of the spliceosome, suggesting that the compromised function of this particle may lead to RP. Here, we report the identification of the p.R192H variant of the tri-snRNP factor PRPF4 in a patient with RP. The mutation affects a highly conserved arginine residue that is crucial for PRPF4 function. Introduction of a corresponding mutation into the zebrafish homolog of PRPF4 resulted in a complete loss of function in vivo. A series of biochemical experiments suggested that p.R192H disrupts the binding interface between PRPF4 and its interactor PRPF3. This interferes with the ability of PRPF4 to integrate into the tri-snRNP, as shown in a human cell line and in zebrafish embryos. These data suggest that the p.R192H variant of PRPF4 represents a functional null allele. The resulting haploinsufficiency of PRPF4 compromises the function of the tri-snRNP, reinforcing the notion that this spliceosomal particle is of crucial importance in the physiology of the retina.

KW - Amino Acid Sequence

KW - Animals

KW - Base Sequence

KW - Blotting, Western

KW - Embryo, Nonmammalian

KW - Gangliosides

KW - Gene Components

KW - HEK293 Cells

KW - Humans

KW - Molecular Sequence Data

KW - Mutation, Missense

KW - Nuclear Proteins

KW - Pedigree

KW - Retinitis Pigmentosa

KW - Ribonucleoprotein, U4-U6 Small Nuclear

KW - Sequence Analysis, DNA

KW - Spliceosomes

KW - Zebrafish

U2 - 10.1371/journal.pone.0111754

DO - 10.1371/journal.pone.0111754

M3 - SCORING: Journal article

C2 - 25383878

VL - 9

SP - e111754

JO - PLOS ONE

JF - PLOS ONE

SN - 1932-6203

IS - 11

ER -